Question: If $6a + 3b = -2$ and $x + 8y + z = -9$, what is $9z + 72y + 60a + 9x + 30b$ ?
$= 60a + 30b + 9x + 72y + 9z$ $= (10) \cdot (6a + 3b) + (9) \cdot (x + 8y + z)$ $= (10) \cdot (-2) + (9) \cdot (-9)$ $= -20 - 81$ $= -101$